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arXiv · 0907.4117

Experimental estimation of entanglement at the quantum limit

Giorgio Brida·Ivo Degiovanni·Angela Florio·Marco Genovese·Paolo Giorda·Alice Meda·Matteo G. A. Paris·Alex Shurupov
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Abstract

Entanglement is the central resource of quantum information processing and the precise characterization of entangled states is a crucial issue for the development of quantum technologies. This leads to the necessity of a precise, experimental feasible measure of entanglement. Nevertheless, such measurements are limited both from experimental uncertainties and intrinsic quantum bounds. Here we present an experiment where the amount of entanglement of a family of two-qubit mixed photon states is estimated with the ultimate precision allowed by quantum mechanics.

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Giorgio Brida, Ivo Degiovanni, Angela Florio, Marco Genovese, Paolo Giorda, Alice Meda, Matteo G. A. Paris, Alex Shurupov. 2009-07-23. Experimental estimation of entanglement at the quantum limit. https://doi.org/10.1103/physrevlett.104.100501

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